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问题 单项选择题

各部门、车间要认真分析管内可能诱发事故的重要因素，明确安全关键卡控重点，督促职工把落实（）措施作为良好的工作习惯。

A.层层落实

B.标准化

C.安全规程

D.关健卡控

答案

参考答案：D

阅读理解

It’s the lunchtime break at Shanghai Xianxia Middle School. No mobile phones can be heard ringing anywhere. The common sight of crowds of children chatting on their phones or sending short messages has disappeared(消失).

A grade-2 student said: “I couldn’t concentrate(集中精力) during classes if the phone was with me. I couldn’t help checking if there were messages or missed phone calls. I even played games on the phone sometimes.”

The school leaders say they feel the ban(禁令) is necessary to keep order in class. They even gave out an open letter to remind parents not to let their children bring mobile phones to school. More than 96 percent of parents say they welcome the school decision. The school is also being flexible（灵活的）in implementing the ban. Those students who live far from school are allowed to bring mobile phones to call their parents. But they still have to turn them off in classrooms.

Medical experts(专家) have also welcomed the school decision. They say too much dependence on mobile phones can cause many psychological problems in school students.

小题1:The passage mainly tells us about___________.

A．whether the mobile phone should be used at school by students

B．the harm the mobile phone may cause to middle school students

C．different opinions between school leaders and medical experts

D．a ban on the use of mobile phones by students in a middle school小题2:In paragraph 3, the underlined word “implementing” means ________in Chinese.

A．调整

B．公布

C．执行

D．张贴
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解答题

Ⅰ．小红的母亲有耳垂、大拇指向背侧弯曲；父亲有耳垂、大拇指不能向背侧弯曲；小红无耳垂、大拇指能向背侧弯曲．请你从①有无耳垂；②大拇指能不能向背侧弯曲两个方面的特征进行分析．

（1）父母有耳垂，小红无耳垂，说明了生物的______现象．

（2）母亲的大拇指指向背侧弯曲，小红的大拇指也能向背侧弯曲，说明了生物的______现象．

（3）以上性状中肯定为隐性性状的是______，肯定为显性性状的是______．

Ⅱ．牛的毛色有黑色和棕色，如果两头黑牛交配产生了一头棕色小牛，请回答．

（1）黑色和棕色哪种是显性性状？______．

（2）如果用B与b表示牛的毛色的显性基因和隐性基因，写出上述两头黑牛的基因组成______．

（3）上述两头黑牛产生一只黑色小牛的可能性是______．

（4）如果用一头雄牛与多头雌牛（基因组成为Bb）交配，共出生20头小牛，全部为黑色，则此雄牛的基因型最可能是______．
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